4.9 Periodic Defective Image
If a mark or other printing defect occurs at regular intervals down the page it may be caused by a damaged or
contaminated roller. Measure the repetition interval and refer to the table below to identify the roller concerned.
No
Roller
Defective image
Typical defect
1
OPC Drum
75.5mm
white spot on black image or black spot
2
Charge Roller
37.8mm
black spot
3
Supply Roller
44.9mm
light or dark horizontal image band
4
Developing Roller
35.2mm
horizontal image band
5
Transfer Roller
45.3mm
image ghost
6
Heat Roller
64.0mm
Black spot and image ghost
7
Pressure Roller
75.3mm
black spot on the backside
SCAN PART
PTL
1
3
7
5
MP Sensor
1
2
3
4
OPC Drum
Charge Roller
Supply Roller
Developing Roller
5
6
7
Tramsfer Roller
Heat Roller
Pressure Roller
<Rollers Layout>
Samsung Electronics
Service Manual
4-9
Alignment and Adjustmens